The 5th preview release of Ubuntu Dapper Drake is out on the mirrors. As usual, there are both install and live CD's for PowerPC, x86, and x86-64. "We are now in the final stages of Dapper Drake development. Everything is stabilizing, and Ubuntu 6.04 will certainly be a top-notch professional OS. Now that all of the lower level improvements have been made, it is time to close the hood and rub on a coat of wax. With Flight 5 comes a new and improved Human look-and-feel, a few new GUI power tools, and much more."Update:Screenshot tour.

I can answer to why someone would like Debian packages over RPMs. I have had RPM databases become corrupted several times. Debian packages are far more friendly to third part repositories, with third party RPMs a lot of times it will totally hose your system, and since Debian in general has a ton more packages, you only need a few from third party repositories in general.